RE: ATM center dotting secondaries

["Bertapelle, Ken" <Bertapelle.Ken@tci.com>]

Nils,

Well, yes, I agree.  Nowadays, that's what I do - use the periphery
of the secondary and center it in the inside of the sighting tube.
I don't need or use the cross hairs at all, other than to remind
myself that when I put that little dot on the secondary last year
I didn't quite get it in the center of the mirror.  So, like I
said, who needs the dot?

- KenB

> -----Original Message-----
> From: Nils Olof Carlin [mailto:nilsolof.carlin@telia.com]
> Sent: Tuesday, July 27, 1999 11:00 AM
> To: Bertapelle, Ken; gf; atm
> Subject: SV: ATM center dotting secondaries
> <snip>
> What center? ;-) The mechanical or optical one??
> No kidding, if you center the *periphery* of the secondary 
> using a suitably sized sighting tube in the focuser (as seen 
> inside the inner opening of the sighting tube), the mirror 
> center will be right on the virtual spot - offset and all! 
> And no crosshairs. 
> 
> <snip>
> Nils Olof
> 
>